A lens driving device for a zoom and a multifocus lens housing of a camera, the lens driving device comprising a holding member for holding imaging lenses and having a first helicoid formed relative to the optical axis of the lenses; a rotary member having a second helicoid which is arranged to engage to the first helicoid, the rotary member being arranged to be engaged to the holding member via the two helicoids and rotatably supported relative to the optical axis to a camera housing; a guide member which is provided for either of the holding member or the camera housing and which has two guide surfaces extending in the direction of the optical axis; and supporting members provided for the residual one of the holding member and the camera housing and having at least one pair of rotary members to which the guide surfaces of the guide member are brought into contact, whereby the contact of the guide member and the supporting members prevents the rotation of the holding member and allows the holding member to rectilinearly move in the direction of the optical axis in accordance with the rotation of the rotary member. As a result, the contact between the guide member and the supporting member prevents the rotation of the holding member, allows the holding member to rectilinearly move in the direction of the optical axis of the lens in accordance with the rotation of the rotary member so that the lens group can smoothly rectilinearly moves.